An important step in metal-plating ceramic and ceramic-like substrates is the prior disruption of the substrate's surface in order to clean soiled surfaces and to produce positive roughening by means of special etching media. Only in this way can good adhesion to the substrate of the subsequently applied metal layer, be attained. Such adhesion is partly based on mechanical anchoring and partly on chemical bonding to the surface.
In some cases, such as the production of so-called printed circuits on ceramic substrates, it is necessary for metal-plating to be effected with electrical characteristics which lie within close limits of tolerance. To achieve this, it is particularly important that there always exist an essentially uniform interface layer between the substrate and the metal layer applied thereto. Such an interface layer influences, for example, the so-called electric loss angle of an electrical circuit arrangement.
Thus, there is still a need for an improved process of this type, whereby metal-plating may be accomplished in a reproducible manner with precisely predetermined characteristics, preferably in a cost effective and reliable manner which is easily adaptable to industrial mass production.